linux-kernel - Re: [PATCH] drm/amdgpu: check a user-provided number of BOs in list

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <aedbcd77-3cb6-48a6-b7ec-b2e5d3d0996c@amd.com>
Date: Mon, 14 Apr 2025 11:27:45 +0200
From: Christian König <christian.koenig@....com>
To: Denis Arefev <arefev@...mel.ru>, Alex Deucher <alexander.deucher@....com>
Cc: David Airlie <airlied@...il.com>, Simona Vetter <simona@...ll.ch>,
 amd-gfx@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org,
 linux-kernel@...r.kernel.org, lvc-project@...uxtesting.org,
 stable@...r.kernel.org
Subject: Re: [PATCH] drm/amdgpu: check a user-provided number of BOs in list

Coming back to the original patch.

Am 08.04.25 um 11:17 schrieb Denis Arefev:
> The user can set any value to the variable ‘bo_number’, via the ioctl
> command DRM_IOCTL_AMDGPU_BO_LIST. This will affect the arithmetic
> expression ‘in->bo_number * in->bo_info_size’, which is prone to
> overflow. Add a valid value check.
>
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>
> Fixes: 964d0fbf6301 ("drm/amdgpu: Allow to create BO lists in CS ioctl v3")
> Cc: stable@...r.kernel.org
> Signed-off-by: Denis Arefev <arefev@...mel.ru>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c
> index 702f6610d024..dd30d2426ff7 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c
> @@ -189,6 +189,9 @@ int amdgpu_bo_create_list_entry_array(struct drm_amdgpu_bo_list_in *in,
>  	struct drm_amdgpu_bo_list_entry *info;
>  	int r;
>  
> +	if (!in->bo_number || in->bo_number > UINT_MAX / info_size)
> +		return -EINVAL;
> +

As discussed with Linus the goal here is not to avoid the warning, but rather to apply a reasonable limit.

Since we already use an u16 for the number of BOs in other cases it is probably reasonable to assume that we will never have more than USHRT_MAX number of BOs here as well.

So please change the patch accordingly and hopefully nobody will complain.

Regards,
Christian.

>  	info = kvmalloc_array(in->bo_number, info_size, GFP_KERNEL);
>  	if (!info)
>  		return -ENOMEM;